Washdown device for inserting pipe into granular material



C. E. REISTLE, JR WASH-DOWN DEVICE FOR INSERTING PIPE INTO GRANULAR MATERIAL Filed Sept. 27, 1939 June 8, 1943.

s Q 9 v Cwzl INVENTOR.

ATTORNEY.

Patented June 8, 1943 WASHDOWN INTO DEVICE FOR INSERTING PIPE GRANULAR MATERIAL Carl E. Beistle, In, Houston, Tex, assignor to Standard Oil Development Company, a corporation of Delaware Application September 27, 1939, Serial No. 296,769

2 Claims.

The present invention relates to a device by which a pipe may be inserted into a bed of granular material.

More particularly, the invention consists of a perforated or slotted pipe, to one end of which is attached a perforated point and which is equipped with an inner liner which seals oil the perforations or slots of the pipe while it is being inserted into a granular bed.

It is known in the art of completing wells to surround the screen through which fluid may be produced with a layer of gravel so that fluid from the producing formation flows through the gravel before it passes through the screen and into the tubing. Since it is customary to wash out or ream a cavity in the producing formation before depositing gravel therein, several results are obtained by this procedure. The gravel acts as a filter to keep sand and other material from being carried by the oil against the screen and since this gravel filter has a large surface it allows fluid from the formation to flow therethrough with a smaller pressure drop than it flows through the screen usually attached to the lower end of a string of tubing.

The present invention relates to a device which may be. attached to the end of a string of tubing. By the use of this device after gravel is deposited in the proper position in a bore hole a screen at the lower end of the string of tubing may be washed down into the gravel and an inner liner removed from the screen so that the well may be produced through the screen.

By the use of this device several advantages are obtained over the conventional methods of graveling wells. At the present time it is customary to first set the screen in the well and then deposit gravel about the screen. This involved considerable difilculty in that the gravel is deposited by being entrained in fluid and carried down into the well where the gravel is allowed to settle out of the fluid and the fluid is then removed from the bore hole.

In. carrying out this procedure the gravel sometimes bridges in the casing at a point above which it is desired to deposit the gravel and prevents the cavity from being properly filled with gravel. Then, too, it sometimes happens that gravel carrying a substantial proportion of sand has its flow stopped for a short time and the sand settles out and forms a plug in the tubing. When this occurs, the tubing must be drawn to the surface of the earth in order to have the plug of sand cleaned out before operations may be resumed.

provided with a seating sleeve 2 By the use of the device of the present invention a cavity in the producing formation at the bore hole may be washed out and gravel deposited in the cavity without keeping a stringof tubing fitted at its lower end with a strainer in the bore hole during the operation. In other words, the

- gravel may be first deposited in the hole and then a string of tubing provided with a strainer at its lower end placed in position within the deposited gravel.

Other objects and advantages of the invention may be seen from the following description taken in conjunction with the drawing in which Fig. 1 is an elevation partly in section of the wash-down tool;

Fig. 2 is an elevation partly in section of the packer which fits snugly into the tool shown in Fig.

Fig. 3 is a cross sectional view of the tool shown in Fig. 1 taken along the lines 3-3; and Fig. 4 is a crosssectional view of the packer shown in Fig. 2 along the line 44.

Fig. 5 is a fragmentary view of-the tool used to pull the inner liner shown in Fig. 2 into the perforated pipe of Fig. 1.

In Fig. 1 a wash-down tool is shown having as its central portion a perforated or slotted pipe I at one end and a seating sleeve 3 at its other end. The end of seatingsleeve 2 projects inwardly as shown for reasons which will afterwards appear. The ends of slotted pipe I are provided with threads and attached to one end by means of coupling-41s a slotted point 5., The other end of slotted pipe I is provided with a coupling 6 which is provided with guide fins I. The other end of coupling 6 may be attached to the upper end of a string of tubing by means of the conventional pipe thread shown.

This tool, as above described, will act as a con- 1 ventional screen when attached to the lower end The packer shown in Fig. 2 is .of such a size that it fits snugly into the tool shown in Fig. 1

and forms a seal with seats 2 and 3 thereof to prevent fluid from flowing from the interior of the tool out through slots 8. A tubular metal member 9 is provided with anouter covering III of a suitable material, such as Neoprene" or rubber.

vided with openings I4 which enable the packer to be pulled into position by means of the tool shown in Fig. 5. The end of the packer which is fitted for engagement with a fishing tool contains slots i5 and the circular opening IE to enable fluid to pass into the packer and hence through the tubular member 9. The circumferential dimensions of the packer are such that its end cooperates with sleeves 2 and 3 of the wash-down tool to make a fluid-tight joint therewith, the length of the packer being such that the ends. of the Neoprene" covering ID will rest on some portion of the sleeves 2 and 3.

In using the device, gravel is deposited at the desired position in a well. The point 5 is then removed from the wash-down tool and the packer pulled through coupling 6 into position in the wash-down tool so that its lower end fits snugly against sleeve 2. The packer is pulled into this position by means of the tool shown in Fig. 5,

' lugs 11 of the tool fitting into openings M of the packer and the other end of the tool being attached to a rope or wire to enable the packer to be pulled into the position. The setting tool is then released from the packer by slipping pipe [9 over springs IB' and compressing them so the lugs I1 are disengaged from holes l4. The packer having been pulled into position, the point 5 is replaced on the wash-down tool and the tool attached to a string of tubing by means of coupling 6.

The tubing may then be inserted into the well with the tool at its lower end and lowered until the uppermost part of the gravel is reached. Wash fluid may then be pumped down the tubing and the tubing rotated. The fluid circulation, weight on the wash tool and rotation will force the tool down into the gravel to the desired depth. When the desired'depth is reached, the fluid circulation is stopped and a fishing tool may be run down in the tubing, engaged with fishing means l3, and the packer removed from the well.

When the packer has been removed from the wash-down tool, fluid from the producing formation may be allowed to flow through the gravel and then through slots 8 into the interior of the tubing and thence up the tubing and out of the well. One of the advantages of the present invention is that the packer sleeve may be withdrawn through an oil well pump working barrel. This allows an oil pump working barrel to be attached above the wash-down tool and inserted in the well on the tubing-along with the washdown tool. When this is done, fluid may be pumped from the well after the wash-down tool has been placed and the packer removed.

In the above disclosed modification a packer sleeve has been described which may be mechanically removed from the wash-down tool. As a The tubular member 9 is provided at both ends with slots l I as shown in order to promodification of this device a packer may be cona liner soluble in alkali may be used and then dissolved by means of an alkali. It is also possible to construct the inner liner from an organic material soluble in common solvents, such as aceton or benzene, and then dissolve the liner from the tool by means of these solvents after it has been placed. The dimensions of the device and the shape of the various parts may be altered and still remain within the scope of the present invention.

I'claim: 1. An assembly adapted to be inserted in a bed of granular material comprising, in combination, a tubular member having a perforated median portion and imperforate end portions with one of said end portions arranged to be secured to 'a string of tubing, an annular seat arranged within each end portion of said member and secured thereto in a fluid tight manner, a per- *forated tip secured to the other end portion, a

second member arranged for insertion in said first member and for withdrawal therefrom by longitudinal movement, said second member defining an imperforate conduit of a length at least equal to the distance between said seats of the first member and comprising a rigid tubular body and a deformable packer mounted on said tubular body, said second member being arranged so that it'may be inserted in said first member with the packer contacting both seats to make a fluid tight friction seal therewith, and when so inserted seals of! the perforated portion of said first member whereby fluid entering the assembly from the string of tubing is conducted to the perforated end.

2. An assembly adapted to be inserted in a bed of granular material comprising, in combination, a tubular member having a perforated median portion and imperforate end portions with one of said end portions arranged to be secured to a string of tubing, an annular seat arranged within each end portionof said member and secured thereto in a fluid tight manner, a perforated tip secured to the other end portion, a second tubular member arranged for insertion in said first member and for withdrawal therefrom by longitudinal movement, said second member having a perforated median portion and imperforate end portions, a deformable sleeve mounted on said second member to cover the perforations thereof, means sealing the ends of said sleeve to the imperforate end portions of said second tubular member in a fluid tight manner, said mounted sleeve being arranged so that it may be inserted in said first member with the sleeve contacting both seats to make a fluid tight friction seal therewith and when so inserted seals off the perforated portion of said member whereby fluid entering the assembly from the string of tubing is conducted to the perforated end.

CARL E. REISTLE, JR. 

